US4138229A - Cleaning tape for magnetic head - Google Patents

Cleaning tape for magnetic head Download PDF

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Publication number
US4138229A
US4138229A US05/844,027 US84402777A US4138229A US 4138229 A US4138229 A US 4138229A US 84402777 A US84402777 A US 84402777A US 4138229 A US4138229 A US 4138229A
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particles
cleaning
tape
cleaning tape
magnetic head
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US05/844,027
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Eiichi Tadokoro
Masahiro Utumi
Masaaki Fujiyama
Satoru Takayama
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Fujifilm Holdings Corp
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Fuji Photo Film Co Ltd
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    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/41Cleaning of heads

Definitions

  • This invention relates to a cleaning tape for cleaning a magnetic recording head of a magnetic tape recorder or the like, and more particularly to an improvement in the material used in the cleaning layer of a magnetic head cleaning tape.
  • the magnetic recording material which coats the magnetic recording medium such as a magnetic tape or sheet is partly shaved off by the sticks on the surface of the magnetic recording head (hereinafter referred to simply as "magnetic head") of the recorder during the play thereof. Further, dust in the atmosphere also sticks on the magnetic head during play. The shaved off magnetic recording material and the dust adhering to the magnetic head will deteriorate the quality of the sound or image recorded on the magnetic recording tape or sheet.
  • the cleaning tape is used in the recorder in the same way as a normal recording tape. While the cleaning tape is in use in the recorder, the surface of the cleaning tape rubs the surface of the magnetic head and abrades the surface to remove the material stuck thereon.
  • Japanese Utility Model Public Disclosure No. 55808/1975 discloses a cleaning tape to be used for this purpose in which paper is laminated on a substrate of tape.
  • This tape is disadvantageous in that the cleaning effect is insufficient. Since the binder constituting the magnetic layer of the tape or sheet is very sticky, the recording material stuck on the magnetic head is hard to remove. Therefore, it is very difficult to adequately remove the material by the cleaning tape having a paper layer. Further, in this type of cleaning tape, the fiber of the paper is liable to stick on the magnetic tape or sheet, and this causes dropout in the signal recording or reproduction.
  • Japanese Patent Public Disclosure No. 40504/1975 discloses a cleaning tape which carries on its substrate a cleaning layer containing particles having a diameter of 0.05 to 3 ⁇ dispersed in a binder.
  • This cleaning tape abrades the material stuck on the surface of the magnetic head with the hard particles contained in the cleaning layer thereof. Therefore, this type of cleaning tape has a sufficient cleaning effect.
  • the particles contained are very hard, the surface of the magnetic head itself is scratched thereby.
  • the scratches formed on the surface of the magnetic head in turn scratch the magnetic tape or sheet and the sensitivity and S/N ratio of the recording tape or sheet are apt to be lowered.
  • the formation of the scratches can be prevented by using particles of comparatively low hardness.
  • the cleaning effect cannot be made sufficiently high. It is, therefore, very difficult to find the optimum hardness of the particles in this type of cleaning tape.
  • the primary object of the present invention is to provide a cleaning tape for removing extraneous material stuck on the magnetic head which has a sufficient cleaning effect and which does not scratch the surface of the magnetic head.
  • the cleaning tape in accordance with the present invention is characterized in that the cleaning layer carried on a substrate thereof contains two kinds of particles having different diameters and different hardnesses.
  • the particles of the first kind have a diameter of not more than 5 ⁇ Mohs hardness of not less than 5.5.
  • the particles of the second kind have a diameter of 6 to 200 ⁇ and Mohs hardness of not more than 5.
  • the first kind of particles has a smaller diameter and higher hardness than the second kind, and the second kind of particles has a larger diameter and lower hardness than the first kind.
  • the material stuck on the magnetic head with a high sticking force can be abraded by the first kind of particles having higher hardness.
  • the material stuck on the magnetic head which is easily removable can be removed by the second kind of particles.
  • the cleaning tape in accordance with the present invention has a high cleaning effect.
  • FIGURE is a longitudinal sectional view of a cleaning tape in accordance with the present invention shown together with a magnetic head bearing extraneous material stuck thereon to be removed.
  • the cleaning tape in accordance with the present invention consists of a substrate 10 and a cleaning layer 11 carried thereon.
  • the cleaning layer 11 contains A-particles having a diameter of not more than 5 ⁇ and Mohs hardness of not less than 5.5, and B-particles having a diameter of 6 to 200 ⁇ and Mohs hardness of not more than 5.
  • the A-particles and B-particles are mixed together and dispersed in a binder and applied on the substrate 10 as a cleaning layer 11.
  • the extraneous material 13 adhering to a magnetic head 12 is abraded and removed by hard the A-particles. Since B-particles of larger diameter and lower hardness are mixed with the A-particles, the pressure of contact between the cleaning tape and the magnetic head 12 is lessened by the B-particles. Thus, the material 13 adhering to the magnetic head 12 can be removed by a small force. Therefore, the magnetic head 12 is not scratched while the material 13 is being removed. In other words, the B-particles function not only to lessen the pressure between the cleaning tape and the magnetic head but also to remove the material sticking on the magnetic head with a comparatively small sticking force.
  • the cleaning tape may be provided with a back coating layer to facilitate the feed thereof.
  • the back coating layer should preferably have a surface resistance of not more than 10 8 ohm/cm.
  • the cleaning tape may be connected to an ordinary magnetic recording tape as a leader tape.
  • the magnetic head can be cleaned every time the magnetic recording tape is used for recording or reproduction.
  • the substrate 10 may be used various kinds of plastic film such as polyester film of polyethylene terephthalate (PET) or polyethylene-2,6-naphthalate, film of polyolefine or polypropylene, and cellulose derivative film of cellulose diacetate, cellulose triacetate, cellulose acetate butylate, or cellulose acetate propionate.
  • PET polyethylene terephthalate
  • polyethylene-2,6-naphthalate film of polyolefine or polypropylene
  • cellulose derivative film of cellulose diacetate, cellulose triacetate, cellulose acetate butylate, or cellulose acetate propionate such as polyester film of polyethylene terephthalate (PET) or polyethylene-2,6-naphthalate, film of polyolefine or polypropylene, and cellulose derivative film of cellulose diacetate, cellulose triacetate, cellulose acetate butylate, or cellulose acetate propionate.
  • the diameter of the A-particles should be not more tha 5 ⁇ and preferably be 0.1 to 1 ⁇ from considerations of the cleaning effect and the probability of scratching. If the diameter of the A-particles is too large, the magnetic head is apt to be scratched thereby, and if it is too small the cleaning effect is lowered.
  • the Mohs hardness thereof should be not less than 5.5 and preferably be not less then 6.
  • A-particles can be used SnO 2 , SiO 2 , Fe 2 O 3 , Fe 3 O 4 , TiO 2 , GeO 2 , CrO 3 , Al 2 O 3 , B 4 C, SiC, ZrO 2 and ThO 2 .
  • the A-particles are hard, they are used together with B-particles which have a larger diameter and lower hardness.
  • the diameter of the B-particles should be 6 to 200 ⁇ and should preferably be 50 to 100 ⁇ . If the diameter of the B-particles is too large, the surface of the cleaning layer becomes too rough and the A-particles are prevented from having their effect on the magnetic head, and if it is too small the effect thereof to lessen the pressure of contact between the cleaning tape and the magnetic head is lowered.
  • the Mohs hardness of the B-particles should be not more than 5 and should preferably be not more than 4.
  • B-particles can be used CaCO 3 ,ZnO, Al 2 O 3 ⁇ 4SiO 2 ⁇ H 2 O (agalmatolite), Al 2 O 3 ⁇ 2SiO 2 ⁇ 2H 2 O (kaolinite), 3CaO ⁇ Al 2 O 3 ⁇ 3CaSO 4 ⁇ 31H 2 O, BaSO 4 (natural barium sulfate, precipitated barium sulfate).
  • thermoplastic resins thermosetting resins
  • reactive resins reactive resins and mixtures of these resins
  • thermoplastic resins various copolymers having a molecular weight of 10,000 to 200,000, a softening point of 150° C and a polymerization degree of about 200 to 500 can be used.
  • thermosetting resins and the reactive resins there can be used various known resins having a molecular weight of not more than 200,000 in coating liquid form which is increased to infinity via a condensation or addition reaction when applied in a coat and dried. Further, among these resins, particularly preferred are resins which do not soften or melt until thermal decomposition takes place.
  • the binder is composed of a single or several resins selected from the above described various kinds of resins. Further, to the resin or mixture of resins can be added such additives as a dispersing agent, lubricant and/or abrasive.
  • thermoplastic resins are vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, vinyl chloride-acrylontrile copolymers, acrylic ester-acrylontrile copolymers, acrylic ester-vinylidene chloride copolymers, acrylic ester-styrene copolymers, methacrylic ester-acrylontrile copolymers, methacrylic ester-vinylidene chloride copolymers, methacrylic ester-styrene copolymers, urethane elastomers, e.g., of the thermosetting type such as those comprising a polyether / diamine group, a polyester / diamine group, a polyester / glycol group, a polyether / glycol group, etc., and of the thermoplastic type, e.g., polyvinyl fluoride, vinylidene chloride-acrylontrile copolymers, butadiene-acrylon
  • thermosetting resins are phenol resins, epoxy resins, thermosetting polyurethane resins, urea-formaldehyde resins, melamine-formaldehyde resins, alkyd resins, silicone resins, acrylic functional resins, epoxy-polyamide resins, nitrocellulose-melamine resins, a mixture of a high molecular weight polyester resin with an isocyanate prepolymer, a mixture of a copolymer of methacrylic acid with a diisocyanate prepolymer, a mixture comprising a polyester-polyol and a polyisocyanate, a mixture comprising a low molecular weight glycol, a high molecular weight diol and triphenylmethane triisocyanate, a polyamine resin, mixtures thereof, etc.
  • the mixing weight ratio of the particles to the binder should be from 5:100 to 400:100, and more preferably be 50:100 to 200:100. If the ratio of the particles to the binder is too small, the cleaning effect is insufficient, and if it is too large the particles are apt to fall out of the cleaning layer. Further, the mixing weight ratio of A-particles to B-particles should be 1:100 to 100:1, and more preferably be 1:100 to 1:10.
  • the thickness of the cleaning layer should preferably be not more than 50 ⁇ . If the thickness is too great, the cleaning tape cannot be put into sufficient contact with the surface of the magnetic head.
  • a cleaning layer of 10 ⁇ thickness consisting of a coating liquid having composition (1) as described hereinbelow was applied on a substrate of PET having a thickness of 38 ⁇ .
  • the tape thus prepared was slit into thin tapes of 1/2 inch width.
  • Four kinds of tapes having cleaning layers containing A- and B-particles both of different diameters were thus prepared and numbered as 1001 to 1004, which are shown in Table I.
  • the cleaning tapes were loaded in a video tape recorder having a magnetic recording head bearing a magnetic material adhering thereto. Then, the time required for cleaning the magnetic head, the reproduction sensitivity, S/N ratio and the surface smoothness of the cleaned head were measured. The results of the test were as shown in Table I.
  • composition (2) as described hereinbelow was used to make a specimen No. 2001.
  • the results were as shown in Table 1.
  • composition (1) The A- and B-particles in composition (1) were replaced by those shown in Table 1 at specimen No. 3001. The results were as shown in Table 1.
  • specimens No. 4001 - 4003 employing A-particles only and specimens No. 5001 - 5002 employing B-particles only were prepared.
  • Specimens No. 4001, 4003 and 5001 were prepared on the basis of the coating composition (1), and specimens No. 4002 and 5002 were prepared on the basis of the coating composition (2). The results obtained by these specimens are also shown in Table 1.
  • the length of scratches on the magnetic tape played after cleaning were measured through microscopic observation. When the length of the scratching was 2 ⁇ or more, it was defined as “Scratching Observed”. When the length was less than 2 ⁇ , it was defined as “None Observed”.
  • the magnetic video tape used in the above tests was prepared by applying on a substrate of 22 ⁇ thickness a magnetic recording layer of 6.5 ⁇ thickness consisting of the following composition (3).

Abstract

A cleaning tape used for cleaning the surface of a magnetic recording head of a tape recorder or the like consists of a substrate and a cleaning layer. The cleaning layer contains two kinds of particles. One kind of particles has a small diameter and a high hardness, and the other has a large diameter and a low hardness.

Description

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a cleaning tape for cleaning a magnetic recording head of a magnetic tape recorder or the like, and more particularly to an improvement in the material used in the cleaning layer of a magnetic head cleaning tape.
2. Description of the Prior Art
In a magnetic tape recorder a video tape recorder, video sheet recorder or the like, the magnetic recording material which coats the magnetic recording medium such as a magnetic tape or sheet is partly shaved off by the sticks on the surface of the magnetic recording head (hereinafter referred to simply as "magnetic head") of the recorder during the play thereof. Further, dust in the atmosphere also sticks on the magnetic head during play. The shaved off magnetic recording material and the dust adhering to the magnetic head will deteriorate the quality of the sound or image recorded on the magnetic recording tape or sheet.
In order to remove the extraneous material stuck on the magnetic head, it has been known to use a cleaning tape. The cleaning tape is used in the recorder in the same way as a normal recording tape. While the cleaning tape is in use in the recorder, the surface of the cleaning tape rubs the surface of the magnetic head and abrades the surface to remove the material stuck thereon.
Japanese Utility Model Public Disclosure No. 55808/1975 discloses a cleaning tape to be used for this purpose in which paper is laminated on a substrate of tape. This tape is disadvantageous in that the cleaning effect is insufficient. Since the binder constituting the magnetic layer of the tape or sheet is very sticky, the recording material stuck on the magnetic head is hard to remove. Therefore, it is very difficult to adequately remove the material by the cleaning tape having a paper layer. Further, in this type of cleaning tape, the fiber of the paper is liable to stick on the magnetic tape or sheet, and this causes dropout in the signal recording or reproduction.
Japanese Patent Public Disclosure No. 40504/1975 discloses a cleaning tape which carries on its substrate a cleaning layer containing particles having a diameter of 0.05 to 3μ dispersed in a binder. This cleaning tape abrades the material stuck on the surface of the magnetic head with the hard particles contained in the cleaning layer thereof. Therefore, this type of cleaning tape has a sufficient cleaning effect. However, since the particles contained are very hard, the surface of the magnetic head itself is scratched thereby. The scratches formed on the surface of the magnetic head in turn scratch the magnetic tape or sheet and the sensitivity and S/N ratio of the recording tape or sheet are apt to be lowered. The formation of the scratches can be prevented by using particles of comparatively low hardness. However, if the hardness is too low, the cleaning effect cannot be made sufficiently high. It is, therefore, very difficult to find the optimum hardness of the particles in this type of cleaning tape.
SUMMARY OF THE INVENTION
In view of the defects inherent in the conventional cleaning tape, the primary object of the present invention is to provide a cleaning tape for removing extraneous material stuck on the magnetic head which has a sufficient cleaning effect and which does not scratch the surface of the magnetic head.
The cleaning tape in accordance with the present invention is characterized in that the cleaning layer carried on a substrate thereof contains two kinds of particles having different diameters and different hardnesses. The particles of the first kind have a diameter of not more than 5μ Mohs hardness of not less than 5.5. The particles of the second kind have a diameter of 6 to 200μ and Mohs hardness of not more than 5. The first kind of particles has a smaller diameter and higher hardness than the second kind, and the second kind of particles has a larger diameter and lower hardness than the first kind. By the second kind of particles having a larger diameter and lower hardness, the pressure of contact between the first kind of particles having a higher hardness and the surface of the magnetic head is lessened. Therefore, the magnetic head is prevented from being scratched. The material stuck on the magnetic head with a high sticking force can be abraded by the first kind of particles having higher hardness. The material stuck on the magnetic head which is easily removable can be removed by the second kind of particles. Thus, the cleaning tape in accordance with the present invention has a high cleaning effect.
BRIEF DESCRIPTION OF THE DRAWING
A single FIGURE is a longitudinal sectional view of a cleaning tape in accordance with the present invention shown together with a magnetic head bearing extraneous material stuck thereon to be removed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Now the present invention will be described in detail with reference to the accompanying drawing. As shown in the drawing, the cleaning tape in accordance with the present invention consists of a substrate 10 and a cleaning layer 11 carried thereon. The cleaning layer 11 contains A-particles having a diameter of not more than 5μ and Mohs hardness of not less than 5.5, and B-particles having a diameter of 6 to 200μ and Mohs hardness of not more than 5. The A-particles and B-particles are mixed together and dispersed in a binder and applied on the substrate 10 as a cleaning layer 11.
The extraneous material 13 adhering to a magnetic head 12 is abraded and removed by hard the A-particles. Since B-particles of larger diameter and lower hardness are mixed with the A-particles, the pressure of contact between the cleaning tape and the magnetic head 12 is lessened by the B-particles. Thus, the material 13 adhering to the magnetic head 12 can be removed by a small force. Therefore, the magnetic head 12 is not scratched while the material 13 is being removed. In other words, the B-particles function not only to lessen the pressure between the cleaning tape and the magnetic head but also to remove the material sticking on the magnetic head with a comparatively small sticking force.
The cleaning tape may be provided with a back coating layer to facilitate the feed thereof. The back coating layer should preferably have a surface resistance of not more than 108 ohm/cm.
The cleaning tape may be connected to an ordinary magnetic recording tape as a leader tape. In this case, the magnetic head can be cleaned every time the magnetic recording tape is used for recording or reproduction.
As the substrate 10 may be used various kinds of plastic film such as polyester film of polyethylene terephthalate (PET) or polyethylene-2,6-naphthalate, film of polyolefine or polypropylene, and cellulose derivative film of cellulose diacetate, cellulose triacetate, cellulose acetate butylate, or cellulose acetate propionate.
The diameter of the A-particles should be not more tha 5μ and preferably be 0.1 to 1μ from considerations of the cleaning effect and the probability of scratching. If the diameter of the A-particles is too large, the magnetic head is apt to be scratched thereby, and if it is too small the cleaning effect is lowered. The Mohs hardness thereof should be not less than 5.5 and preferably be not less then 6.
As the A-particles can be used SnO2, SiO2, Fe2 O3, Fe3 O4, TiO2, GeO2, CrO3, Al2 O3, B4 C, SiC, ZrO2 and ThO2.
Since the A-particles are hard, they are used together with B-particles which have a larger diameter and lower hardness. The diameter of the B-particles should be 6 to 200μ and should preferably be 50 to 100μ. If the diameter of the B-particles is too large, the surface of the cleaning layer becomes too rough and the A-particles are prevented from having their effect on the magnetic head, and if it is too small the effect thereof to lessen the pressure of contact between the cleaning tape and the magnetic head is lowered. The Mohs hardness of the B-particles should be not more than 5 and should preferably be not more than 4.
As B-particles can be used CaCO3,ZnO, Al2 O3 ·4SiO2 ·H2 O (agalmatolite), Al2 O3 ·2SiO2 ·2H2 O (kaolinite), 3CaO·Al2 O3 ·3CaSO4 ·31H2 O, BaSO4 (natural barium sulfate, precipitated barium sulfate).
As the binder in which the A-particles and the B-particles are dispersed, various binders used in conventional magnetic tapes such as thermoplastic resins, thermosetting resins, reactive resins and mixtures of these resins can be used.
As the thermoplastic resins, various copolymers having a molecular weight of 10,000 to 200,000, a softening point of 150° C and a polymerization degree of about 200 to 500 can be used. As the thermosetting resins and the reactive resins, there can be used various known resins having a molecular weight of not more than 200,000 in coating liquid form which is increased to infinity via a condensation or addition reaction when applied in a coat and dried. Further, among these resins, particularly preferred are resins which do not soften or melt until thermal decomposition takes place. The binder is composed of a single or several resins selected from the above described various kinds of resins. Further, to the resin or mixture of resins can be added such additives as a dispersing agent, lubricant and/or abrasive.
Specific examples of the thermoplastic resins are vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinylidene chloride copolymers, vinyl chloride-acrylontrile copolymers, acrylic ester-acrylontrile copolymers, acrylic ester-vinylidene chloride copolymers, acrylic ester-styrene copolymers, methacrylic ester-acrylontrile copolymers, methacrylic ester-vinylidene chloride copolymers, methacrylic ester-styrene copolymers, urethane elastomers, e.g., of the thermosetting type such as those comprising a polyether / diamine group, a polyester / diamine group, a polyester / glycol group, a polyether / glycol group, etc., and of the thermoplastic type, e.g., polyvinyl fluoride, vinylidene chloride-acrylontrile copolymers, butadiene-acrylonitrile copolymers, polyamide resins, e.g., poly-condensates of the dicarboxylic acid and a diamine, polycondensates of ω-aminocarboxylic acid aromatic polyamides, etc., polyvinyl butyral, cellulose derivatives (e.g., cellulose acetate butyrate, cellulose diacetate, cellulose triacetate, cellulose propionate, nitrocellulose), styrene-butadiene copolymers, polyester resins, e.g., polyethylene terephthalate, urethane rubber, polyurethane and the like, chloro-vinyl etheracrylic ester copolymers, various synthetic rubbers, e.g., BR (butadiene rubber), IR (isoprene rubber), CR (chloroprene rubber), ABR (acrylate butadiene rubber), IIR (isobutene-isoprene rubber), NBR (nitrile-butadiene rubber), NCR (nitrile-chloroprene rubber), PBR (pyridine-butadiene rubber), SBR (styrene-butadiene rubber), SCR (styrene-chloroprene rubber), SIR (styrene-isoprene rubber), etc. and mixtures thereof.
Specific examples of the thermosetting resins are phenol resins, epoxy resins, thermosetting polyurethane resins, urea-formaldehyde resins, melamine-formaldehyde resins, alkyd resins, silicone resins, acrylic functional resins, epoxy-polyamide resins, nitrocellulose-melamine resins, a mixture of a high molecular weight polyester resin with an isocyanate prepolymer, a mixture of a copolymer of methacrylic acid with a diisocyanate prepolymer, a mixture comprising a polyester-polyol and a polyisocyanate, a mixture comprising a low molecular weight glycol, a high molecular weight diol and triphenylmethane triisocyanate, a polyamine resin, mixtures thereof, etc.
The mixing weight ratio of the particles to the binder should be from 5:100 to 400:100, and more preferably be 50:100 to 200:100. If the ratio of the particles to the binder is too small, the cleaning effect is insufficient, and if it is too large the particles are apt to fall out of the cleaning layer. Further, the mixing weight ratio of A-particles to B-particles should be 1:100 to 100:1, and more preferably be 1:100 to 1:10.
The thickness of the cleaning layer should preferably be not more than 50μ. If the thickness is too great, the cleaning tape cannot be put into sufficient contact with the surface of the magnetic head.
Now the present invention will be described with reference to several examples thereof.
EXAMPLE 1
A cleaning layer of 10μ thickness consisting of a coating liquid having composition (1) as described hereinbelow was applied on a substrate of PET having a thickness of 38μ. The tape thus prepared was slit into thin tapes of 1/2 inch width. Four kinds of tapes having cleaning layers containing A- and B-particles both of different diameters were thus prepared and numbered as 1001 to 1004, which are shown in Table I. The cleaning tapes were loaded in a video tape recorder having a magnetic recording head bearing a magnetic material adhering thereto. Then, the time required for cleaning the magnetic head, the reproduction sensitivity, S/N ratio and the surface smoothness of the cleaned head were measured. The results of the test were as shown in Table I.
              Composition (1)                                             
______________________________________                                    
A-particles (Cr.sub.2 O.sub.3)                                            
                             200 g                                        
B-particles (CaCO.sub.2)     100 g                                        
vinylchloride-vinylidene chloride copolymer                               
(copolymerization ratio = 7 : 3, degree of                                
polymerization = 400)        46.4 g                                       
epoxy resin (reaction product of bisphenol A                              
and epichlorohydrine, molecular weight = 900,                             
epoxy equivalent = 460-520,                                               
hydroxyl group content = 0.29%, Epicoat 1001 made                         
by Shell Oil Co.)            28.3 g                                       
silicone oil (dimethylpolysiloxane)                                       
                              0.4 g                                       
isocyanate compound (75 wt % of ethyl acetate solution                    
of a reaction product of 3 mols of 2,4-tolylenediisocyanate               
and 1 mol of trimethylolpropane, Desmodur L-75 made                       
by Bayer A.G)                 5.6 g                                       
butyl acetate                800 g                                        
______________________________________                                    
EXAMPLE 2
Instead of composition (1), composition (2) as described hereinbelow was used to make a specimen No. 2001. The results were as shown in Table 1.
              Composition (2)                                             
______________________________________                                    
A-particles (SiO.sub.2)       50 g                                        
B-particles (ZnO)            250 g                                        
vinylchloride-vinylidene chloride copolymer                               
(copolymerization ratio = 87 : 13, degree of                              
polymerization = 350)        34.7 g                                       
polyester polyol             21 g                                         
(reaction product of 1 mol of adipic acid, 1 mol of                       
diethyleneglycol and 0.06 mol of trymethylolpropane,                      
viscosity (at 75° C.) 1000 cp, specific gravity 1.18               
OH-value 60, acid value < 2)                                              
soybean lecithin              0.2 g                                       
silicone oil (dimethylpolysiloxane)                                       
                              0.1 g                                       
polyisocyanate (75 wt % of ethyl acetate solution                         
of a reaction product of 3 mols of 2,4-tolylenediisocyanate               
and 1 mol of trimethylolpropane, Desmodur L-75 made                       
by Bayer A.G)                 18 g                                        
methyl ethyl keton           400 g                                        
toluene                      400 g                                        
______________________________________                                    
EXAMPLE 3
The A- and B-particles in composition (1) were replaced by those shown in Table 1 at specimen No. 3001. The results were as shown in Table 1.
COMPARISON
In order to compare the results obtained by the clening tape containing two kinds of particles in accordance with this invention with those obtained by a cleaning tape containing only one kind of particles, specimens No. 4001 - 4003 employing A-particles only and specimens No. 5001 - 5002 employing B-particles only were prepared. Specimens No. 4001, 4003 and 5001 were prepared on the basis of the coating composition (1), and specimens No. 4002 and 5002 were prepared on the basis of the coating composition (2). The results obtained by these specimens are also shown in Table 1.
In Table 1, the measured factors are defined as follows.
(1) Time required for cleaning
The time required for cleaning the magnetic head to a degree of cleanness at which no dropout is observed in the reproduced image.
(2) Reproduction sensitivity and S/N ratio
Relative values in dB to an output (0dB) of 4 MHz measured before cleaning.
(3) Surface smoothness
The length of scratches on the magnetic tape played after cleaning were measured through microscopic observation. When the length of the scratching was 2μ or more, it was defined as "Scratching Observed". When the length was less than 2μ, it was defined as "None Observed".
The magnetic video tape used in the above tests was prepared by applying on a substrate of 22μ thickness a magnetic recording layer of 6.5μ thickness consisting of the following composition (3).
              Composition (3)                                             
______________________________________                                    
magnetic particles (γ-Fe.sub.2 O.sub.3) (size 0.02μ×0.12.mu
.,                                                                        
Hc : 2800e)                  300 g                                        
vinylchloride-vinylidene chloride copolymer                               
(copolymerization ratio = 87 : 13, degree of                              
polymerization = 350)        22.4 g                                       
polyester polyol             18.3 g                                       
(reaction product of 1 mol of adipic acid, 1 mol of                       
diethyleneglycol and 0.06 mol oftrymethylolpropane,                       
viscosity (at 75° C.) 1000 cp, specific gravity 1.18               
OH-value 60, acid value < 2)                                              
soybean lecithin              1.2 g                                       
silicone oil (dimethylpolysiloxane)                                       
                              0.4 g                                       
polyisocyanate (75 wt. % of ethyl acetate solution                        
of a reaction product of 3 mols of 2,4-tolylenediisocyanate               
and 1 mol of trimethylolpropane, Desmodur L-75 made                       
by Bayer A.G)                 4.2 g                                       
methyl ethyl keton           400 g                                        
toluene                      400 g                                        
______________________________________                                    
                                  TABLE 1                                 
__________________________________________________________________________
                                   Time                                   
                                   required                               
                                        Reproduc-                         
A-particles         B-particles    for  tion                              
Specimen       Mohs           Mohs cleaning                               
                                        sensitivity                       
                                              S/N                         
                                                 Scratch-                 
No.  Material                                                             
          Size (μ)                                                     
               hardness                                                   
                    Material                                              
                         Size (μ)                                      
                              hardness                                    
                                   (sec)                                  
                                        (dB)  (dB)                        
                                                 ing  Grade               
__________________________________________________________________________
1001 Cr.sub.2 O.sub.3                                                     
          0.8  6    CaCO.sub.2                                            
                         30   3    3-5  +0.8  +0.5                        
                                                 None Good                
1002 "    0.01 6    "    30   3    40   -0.8  -1.4                        
                                                 None Good                
1003 "    0.8  6    "    250  3    over 90                                
                                        -1.2  -1.5                        
                                                 None Bad                 
1004 "    7    6    "    30   3    under 3                                
                                        -0.4  -1.8                        
                                                 Observed                 
                                                      Bad                 
2001 SiO.sub.2                                                            
          3    7    ZnO  100  4.5  3-10 +0.9  +0.6                        
                                                 None Good                
3001 Al.sub.2 O.sub.3                                                     
          3    9    ZnO  100  4.5  "    +0.8  +0.7                        
                                                 None Good                
4001 Cr.sub.2 O.sub.3                                                     
          0.8  6    --   --   --   3-5  +0.1  -1.4                        
                                                 Observed                 
                                                      Bad                 
02   SiO.sub.2                                                            
          3    7    --   --   --   "    -0.2  -1.3                        
                                                 "    Bad                 
03   Al.sub.2 O.sub.3                                                     
          3    9    --   --   --   "    -0.2  -1.6                        
                                                 "    Bad                 
5001 --   --   --   CaCO.sub.2                                            
                         30   3    over 120                               
                                        -2.3  -2.6                        
                                                 None Bad                 
02   --   --   --   ZnO  100  4.5  "    -2.6  -2.9                        
                                                 None Bad                 
__________________________________________________________________________

Claims (10)

We claim:
1. A cleaning tape for cleaning the surface of a magnetic recording head of a magnetic tape recorder or the like comprising a flexible substrate and a cleaning layer disposed thereon, said cleaning layer containing two kinds of particles one of which has a diameter of not more than 5μ and Mohs hardness of not less than 5.5, and the other of which has a diameter of 6 to 200μ and Mohs hardness of not more than 5.
2. A cleaning tape as defined in claim 1 wherein the diameter of said one kind of particles is 0.1 to 1μ.
3. A cleaning tape as defined in claim 1 wherein the Mohs hardness of said one kind of particles is not less than 6.
4. A cleaning tape as defined in claim 1 wherein the diameter of said other kind of particles is 50 to 100μ.
5. A cleaning tape as defined in claim 1 wherein the Mohs hardness of said other kind of particles is not more than 4.
6. A cleaning tape as defined in claim 1 wherein said cleaning layer comprises a binder and said two kinds of particles are dispersed therein.
7. A cleaning tape as defined in claim 6 wherein the mixing weight ratio of said particles to the binder is within the range of 5:100 to 400:100.
8. A cleaning tape as defined in claim 7 wherein the mixing weight ratio of said particles to the binder is within the range of 50:100 to 200:100.
9. A cleaning tape as defined in claim 6 wherein the mixing weight ratio of said two kinds of particles is within the range of 1:100 to 100:1.
10. A cleaning tape as defined in claim 9 wherein the mixing weight ratio of said one kind of particles to said the other kind of particles is within the range of 1:100 to 1:10.
US05/844,027 1976-12-21 1977-10-20 Cleaning tape for magnetic head Expired - Lifetime US4138229A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP51-153657 1976-12-21
JP15365776A JPS5377612A (en) 1976-12-21 1976-12-21 Cleaning tape for magnetic recorder

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Publication Number Publication Date
US4138229A true US4138229A (en) 1979-02-06

Family

ID=15567317

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US05/844,027 Expired - Lifetime US4138229A (en) 1976-12-21 1977-10-20 Cleaning tape for magnetic head

Country Status (4)

Country Link
US (1) US4138229A (en)
JP (1) JPS5377612A (en)
DE (1) DE2751135C2 (en)
GB (1) GB1553550A (en)

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4266256A (en) * 1977-06-24 1981-05-05 Hitachi, Ltd. Cleaner ribbon for magnetic tape
US4422119A (en) * 1980-07-28 1983-12-20 Yoshio Kawakami Leader tape
US4435160A (en) 1980-07-25 1984-03-06 Minnesota Mining And Manufacturing Company Method and manufacture for applying and removal of orthodontic bracket
US4490762A (en) * 1980-03-21 1984-12-25 Fuji Photo Film Co., Ltd. Cleaning tape
US4609382A (en) * 1984-02-11 1986-09-02 Hoechst Aktiengesellschaft Solids concentrate which contains abrasive solids and causes little wear
US4644703A (en) * 1986-03-13 1987-02-24 Norton Company Plural layered coated abrasive
US4652958A (en) * 1984-11-20 1987-03-24 Fuji Photo Film Co., Ltd. Tape for cleaning magnetic head
US4695251A (en) * 1980-04-07 1987-09-22 Minnesota Mining And Manufacturing Company Orthodontic bracket adhesive and abrasive for removal thereof
US4767644A (en) * 1986-04-18 1988-08-30 Fuji Photo Film Co., Ltd. Method of making abrasive tape
US4906185A (en) * 1980-04-07 1990-03-06 Minnesota Mining And Manufacturing Company Orthodontic bracket adhesive and abrasive for removal thereof
US5011511A (en) * 1988-07-27 1991-04-30 Alexander Beck Grinding tool
US5036629A (en) * 1988-04-19 1991-08-06 Fuji Photo Film Co., Ltd. Method for preparing a magnetic recording medium
US5127924A (en) * 1991-07-01 1992-07-07 Russell Jeffrey D Hard particle coated grinding wheel
US5135546A (en) * 1989-08-10 1992-08-04 Fuji Photo Film Co., Ltd. Abrasive tape
US5256497A (en) * 1990-07-12 1993-10-26 Basf Magnetics Gmbh Magnetic tape containing abrasives
US5456734A (en) * 1993-05-07 1995-10-10 Fuji Photo Film Co., Ltd. Abrasive member
US5611826A (en) * 1994-03-01 1997-03-18 Fuji Photo Film Co., Ltd. Abrasive tape
US5633068A (en) * 1994-10-14 1997-05-27 Fuji Photo Film Co., Ltd. Abrasive tape having an interlayer for magnetic head cleaning and polishing
US5672185A (en) * 1995-04-27 1997-09-30 Fuji Photo Film Co., Ltd. Abrasive member
US5702800A (en) * 1995-03-30 1997-12-30 Fuji Photo Film Co., Ltd. Abrasive tape for magnetic information reading apparatus for photographic use, abrasive tape package, and a method for cleaning the apparatus
US5711772A (en) * 1995-03-30 1998-01-27 Fuji Photo Film Co., Ltd. Abrasive member
US5991127A (en) * 1996-08-21 1999-11-23 Geneva Group Of Companies, Inc. Magnetic head and tape path cleaning tape
WO2000051788A1 (en) * 1999-03-05 2000-09-08 3M Innovative Properties Company Abrasive articles having bond systems containing abrasive particles
US20020134407A1 (en) * 2001-03-22 2002-09-26 Nec Corporation Magnetic head cleaning tape and cleaning method for magnetic heads
US20050129446A1 (en) * 2003-12-16 2005-06-16 Jennifer Johnson Thermal printing and cleaning assembly
WO2011149625A2 (en) * 2010-05-25 2011-12-01 3M Innovative Properties Company Layered particle electrostatic deposition process for making a coated abrasive article
WO2019113040A1 (en) * 2017-12-04 2019-06-13 Worldwide Green Holdings Llc Composition for cleaning and coating non-porous surfaces

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* Cited by examiner, † Cited by third party
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CA1238805A (en) * 1980-04-07 1988-07-05 Ronald M. Randklev Orthodontic bracket adhesive and abrasive for removal thereof
JPS578917A (en) * 1980-06-20 1982-01-18 Tdk Corp Cleaning tape for magnetic recorder
JPS5712411A (en) 1980-06-24 1982-01-22 Fuji Photo Film Co Ltd Cleaning tape
US4635154A (en) * 1983-12-23 1987-01-06 Allsop, Inc. Cleaning ribbon and method for cleaning a video player/recorder
US4661874A (en) * 1984-06-01 1987-04-28 International Jensen Incorporated Low friction cleaner for magnetic transducer head
JPH06101102B2 (en) * 1985-03-30 1994-12-12 ソニー株式会社 Cleaning disk
GB2219123B (en) * 1988-04-18 1992-09-30 Tandy Corp Magnetic head cleaning material
US5012377A (en) * 1988-04-18 1991-04-30 Tandy Corporation Homogeneous magnetic head cleaning material
JPH0641110B2 (en) * 1990-01-22 1994-06-01 ソマール株式会社 Method of manufacturing polishing film

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US3069815A (en) * 1958-10-02 1962-12-25 Ibm Cleaning tape for information sensing apparatus
US3266878A (en) * 1962-07-23 1966-08-16 Norton Co Coated abrasives
US3383191A (en) * 1965-06-03 1968-05-14 Simonds Abrasive Company Diamond abrasive article containing hexagonal crystalline boron nitride particles
US3476537A (en) * 1966-05-23 1969-11-04 Acme Abrasive Co Abrasive composition with limestone as the porosity-inducing agent
US3978520A (en) * 1974-11-29 1976-08-31 Minnesota Mining And Manufacturing Company Magnetic head cleaning tape and method

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Publication number Priority date Publication date Assignee Title
US3069815A (en) * 1958-10-02 1962-12-25 Ibm Cleaning tape for information sensing apparatus
US3266878A (en) * 1962-07-23 1966-08-16 Norton Co Coated abrasives
US3383191A (en) * 1965-06-03 1968-05-14 Simonds Abrasive Company Diamond abrasive article containing hexagonal crystalline boron nitride particles
US3476537A (en) * 1966-05-23 1969-11-04 Acme Abrasive Co Abrasive composition with limestone as the porosity-inducing agent
US3978520A (en) * 1974-11-29 1976-08-31 Minnesota Mining And Manufacturing Company Magnetic head cleaning tape and method

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4266256A (en) * 1977-06-24 1981-05-05 Hitachi, Ltd. Cleaner ribbon for magnetic tape
US4490762A (en) * 1980-03-21 1984-12-25 Fuji Photo Film Co., Ltd. Cleaning tape
US4906185A (en) * 1980-04-07 1990-03-06 Minnesota Mining And Manufacturing Company Orthodontic bracket adhesive and abrasive for removal thereof
US4695251A (en) * 1980-04-07 1987-09-22 Minnesota Mining And Manufacturing Company Orthodontic bracket adhesive and abrasive for removal thereof
US4435160A (en) 1980-07-25 1984-03-06 Minnesota Mining And Manufacturing Company Method and manufacture for applying and removal of orthodontic bracket
US4422119A (en) * 1980-07-28 1983-12-20 Yoshio Kawakami Leader tape
US4609382A (en) * 1984-02-11 1986-09-02 Hoechst Aktiengesellschaft Solids concentrate which contains abrasive solids and causes little wear
US4652958A (en) * 1984-11-20 1987-03-24 Fuji Photo Film Co., Ltd. Tape for cleaning magnetic head
US4644703A (en) * 1986-03-13 1987-02-24 Norton Company Plural layered coated abrasive
US4767644A (en) * 1986-04-18 1988-08-30 Fuji Photo Film Co., Ltd. Method of making abrasive tape
US5036629A (en) * 1988-04-19 1991-08-06 Fuji Photo Film Co., Ltd. Method for preparing a magnetic recording medium
US5011511A (en) * 1988-07-27 1991-04-30 Alexander Beck Grinding tool
US5135546A (en) * 1989-08-10 1992-08-04 Fuji Photo Film Co., Ltd. Abrasive tape
US5256497A (en) * 1990-07-12 1993-10-26 Basf Magnetics Gmbh Magnetic tape containing abrasives
US5127924A (en) * 1991-07-01 1992-07-07 Russell Jeffrey D Hard particle coated grinding wheel
US5456734A (en) * 1993-05-07 1995-10-10 Fuji Photo Film Co., Ltd. Abrasive member
US5611826A (en) * 1994-03-01 1997-03-18 Fuji Photo Film Co., Ltd. Abrasive tape
US5633068A (en) * 1994-10-14 1997-05-27 Fuji Photo Film Co., Ltd. Abrasive tape having an interlayer for magnetic head cleaning and polishing
US5702800A (en) * 1995-03-30 1997-12-30 Fuji Photo Film Co., Ltd. Abrasive tape for magnetic information reading apparatus for photographic use, abrasive tape package, and a method for cleaning the apparatus
US5711772A (en) * 1995-03-30 1998-01-27 Fuji Photo Film Co., Ltd. Abrasive member
US5672185A (en) * 1995-04-27 1997-09-30 Fuji Photo Film Co., Ltd. Abrasive member
US5991127A (en) * 1996-08-21 1999-11-23 Geneva Group Of Companies, Inc. Magnetic head and tape path cleaning tape
WO2000051788A1 (en) * 1999-03-05 2000-09-08 3M Innovative Properties Company Abrasive articles having bond systems containing abrasive particles
US20020134407A1 (en) * 2001-03-22 2002-09-26 Nec Corporation Magnetic head cleaning tape and cleaning method for magnetic heads
US20050129445A1 (en) * 2003-12-16 2005-06-16 Jennifer Johnson Thermal printing and cleaning assembly
US20050129446A1 (en) * 2003-12-16 2005-06-16 Jennifer Johnson Thermal printing and cleaning assembly
US20050128280A1 (en) * 2003-12-16 2005-06-16 Jennifer Johnson Thermal printing and cleaning assembly
US6908240B1 (en) 2003-12-16 2005-06-21 International Imaging Materials, Inc Thermal printing and cleaning assembly
US7156566B2 (en) 2003-12-16 2007-01-02 International Imaging Materials, Inc. Thermal printing and cleaning assembly
US7182532B2 (en) 2003-12-16 2007-02-27 International Imaging Materials, Inc. Thermal printing and cleaning assembly
WO2011149625A2 (en) * 2010-05-25 2011-12-01 3M Innovative Properties Company Layered particle electrostatic deposition process for making a coated abrasive article
WO2011149625A3 (en) * 2010-05-25 2012-02-02 3M Innovative Properties Company Layered particle electrostatic deposition process for making a coated abrasive article
US8551577B2 (en) 2010-05-25 2013-10-08 3M Innovative Properties Company Layered particle electrostatic deposition process for making a coated abrasive article
US8869740B2 (en) 2010-05-25 2014-10-28 3M Innovative Properties Company Layered particle electrostatic deposition process for making a coated abrasive article
WO2019113040A1 (en) * 2017-12-04 2019-06-13 Worldwide Green Holdings Llc Composition for cleaning and coating non-porous surfaces

Also Published As

Publication number Publication date
DE2751135C2 (en) 1986-11-27
JPS5377612A (en) 1978-07-10
DE2751135A1 (en) 1978-06-22
JPS6213723B2 (en) 1987-03-28
GB1553550A (en) 1979-09-26

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